At least Voyager tried something different with multiple cubes and so on making an appearance at various points.

Agreed. It was another Catch-22 for VOY.

If they would have only used one cube, they would have been grilled for being unoriginal, denying the audience something new, and just copying TNG.

Perhaps the real problem was the concept of the Queen herself. That changed the Borg more than the quantity of cubes. It muddied the waters and no one ever quite knew the exact boundaries of the Queen's existence because First Contact didn't really explain it.

Instead of being a unique faceless villain, the Borg were normalized in a way. VOY didn't make that change; it was forced to react to it.

After "Scorpion," I wish the show's main villain would have been 8472.